mutscheller



Feb. 26, 1924; 1,484,663

' A. MUTSCHELLER .X-RAY FILTER Filed Sept. 16. 1921 5 sheets-sheet 1 IEURE l 2 Y Mm t E e A m R 4 s m A. MUTSCHELLER X-RAY FILTER Filed Sept.16

Feb; 26. .1924. r 1,484,663

' A. MUTSCHELLER X-RAY FILTER Filed Sept. 16 1921 5 Sheets-Sheet A TTORAEY v Few-2s. 1924; 1,484,663

A. MUTSCHELLER X-RAY FILTER Filed Sept. 16 1921 5 Sheets-Sheet 4 VZWIJGL I hw .4 rrom'zy Feb. 26; 1924;

A. MUTSCHELLER x-mvz nurrm Filed se als. 1921 Patented Feb. 26, 1924.

UNITED STATES PATENT. oEricj-E.

ARTHUR MUTSOHELLERgOF NEW YORK, N. Y.',-ASSIGNOB TO'WAPPLER ELEG'I'RIO co mo, A CORPORATION OF NEW YORK:

X-RAY FILTER Application filed September 16, 1921., Serial No. 501,091;

To all whom it may concern:

Be it known that I, ARTHUR MIUTSCHEL- LER, a citizen of the United States, residing in the city of New York, county of'New York, and State of New York,-have invented certain new and useful Improvements in X-Ray Filters, of which the following is a full, clear, and concise description.

My invention relates to X-ray filters; that is to devices used in connection with X-ray tubes, for the purpose of, preventing secondary X-rays from reaching an object to be operated upon by the primary X-rays, and yet allowing the primary rays to reach the object with facility. I

More particularly stated, by my invention, I seek to improve upon X-ray filters of the type heretofore used for ,the purpose of re. ducing the amount=Of' fogging upon X-ray; 0. plates and fluoroscopic screens: a

X.-ray filters of the kind here contemplated-have oftenpbeen usedin medical X: ray and-fluorgraphic work; that is,I where a photograph was to; be made so as to' exhibit' the. bony structure of a patients body or; a part thereof, the idea being to intercept as far as practicable such of the secondary X-rays as tended to reachthe plate, and yet allowing. the primary, rays, as far. as 3 practicable to structed. y

All X-ray-filters heretofore employed in practice have been based upon theidea-tha-t, since the X-rays alwaystend to Itravel in straight lines and are never, to anyinate rial extent at least, either reflected or refi'acted', and .since the secondary rays are given off by the bony parts of the body when such parts are exposed to the action of the 40 primary X-rays, a large proportion of the secondary X-rays necessarily travel in directions different from those of the primary X-rays, so that under suitable conditions the secondary rays may be intercepted While the primary rays are allowed to pass freely. This has been accomplished by means of a grid provided with openings so arranged as to allow the primary rays to pass through it in the simplest manner possible, the grid being of a somewhat cellular form and thus provided with partitions made of metal or other material opaque to X-rays and so arranged as to its position relatively to the patients body or the part thereof to be photographoi'l, that the secondary rays are pass through the filter unob-,

in great measure intercepted for the-reason that they tend to passjthrough the filter in radial directions suchas-to causethemtobe obstructed by the partitions ,of the-{filten lVith such an arrangement, secondary rays are intercepted to -a.greater;extonfi thanpri; mary rays, for the simple reason; that while the primary rays are, a l projected from the anti-cathode or target of anaXsz-aytube and consequently radiate practica ly; ivii'bm a single; point, the secondary rays-Q-arwprm jected in practically alldirections and'ifrom an infinite number of points all ofiwhich, being ,within the patients body 110 .21 pa t'ato b p ot graph r i' s p rd st nce away from the source of, primary rays,;.and hence the interception of, a large prolporigion of the secondary rays ca nbe accomp whorl-without a proportionate nt 'mepi on eiitheprimarys r y a. .In. o r wnr seazpri ryirayrmay have such direction-ithatdt can passaireely through an opening,- whereas a. secondary, ray, ,originatin g at a point,- isome 1; distance away from ithe. souroe,- of.r;the primary-may; maydiave {su h-t ifipni aite. prevent; i from finding its gway the .O suing; In some .in stances, the ,xrl'fiyjg j teak-has been, curved, 7 its; curvature 5a ,progimating tha of am ter spliere sawhead relatively to the X-ray tube to ithetarget intogthe center of curvature'iog 'the filter; Theiopenings in the filterfihave =usu-v ally be'en merely cellular} Openings ;mor e' ior less analogous .in' form t'o thev com artrnents' of. a box for-shippingg s. 3 The bar while; in active use rnust be fiept, in motion, in order to prevent tlf16'-CR. StlI1g;;Of 3.filladOW; upon the sensitive plate.

In other instances, the filter: carries a num-Q ber ofstrips -;disposed parallel L with?" each other and each extending edge wise-1 in a dig rection-radial to the target of vthe X-ray tubeas azcenter. The filtergjust mentioned-[mustalso be moved continuously While in use, ins order to-prevent the casting. of a shadow.-

lVith filters of the twotypesjust mentioned, it is necessary to maintain a considerable distance between the patienfisbody or other object to be photographed and the" sensitive plate to be exposed to the'X-rays. Because of the distance required for the purpose just indicated, the photographic results have not been very satisfactory, the plate frequently exhibiting a considerable amount of blurring. Again-it has been found almost impossible to confer u on the filter slich a motion as to prevent t aformation of a shadow of some sort upon the late, due to the partitions or other memhers employed for intercepting the secondary rays.

By my invention I seek to remedy, or at least to alleviate, the necessity for the troubles above mentioned. Among the objects sought to be accomplished are the following:

' I. To provide an X-ray filter comprising among other things a grid and means for moving the same bodily While in action, the grid being provided with slats each journaled toturn slightly upon an axis of its own, and to provide means for thus turning the slats, in order to maintain each slat exactly edg'ewise relatively to the position of the target, andfor coordinating the turnin 'movemen't of the slats with the bodily movement of the grid. i

II. To 50 position and arrange the slats just mentioned in the general form of a plane so that the grid e's-a whole is Hat and cafi he brought into relatively close roarin'iity' to the patients body in order too tain sharpness of detail upon the plate, the mechanism for turning'the s'latseach upon its own axis being adapted to actuate said slats when thus arranged in the form of a plane.

III; To provide ineans, controllable at the will of the o erator, for-adjustin the slate of the grid relatively to each other, for the purp se of adepting the-grid for dif-' ferent distances from "the target of the X ray tube, and in'so'doing'to corres ondin'g'ly adjust the turning movements of the res 'etive slats.

To emplo together a plurality of rids of the kind just mentionech movable bodily in directions -c1"os'sing"' each other, the bodily movements of the grids and the turning movements of'the slats thereof being correlated so that the turning movements of the slats being derived from the bodily movements of the grids, are rendered practically automatic.

V. To provide for placing and maintainmg the grids just mentioned as closely as possible to each other. in order to diminish the distance between the patients body and the sensitive plate, the filter being thus adapted to diminish the tiine'otherwise required for exposure.

VI. To provide for operating my improved X-ray filter in connection with a timing apparatus fohcontrollingthe duration of exposure of the plate, so as to cause the period of exposure to begin While the movable parts of the X-ray filter are in actionfiancl to continue until after said movable parts a re brought to rest, thus preventing any blurring from the slats of the grid acting otherwise than By moving uniformly and continuously; in other word pieventing the slats from casting shadows, either sharply defined or nebulous.

VII. To make provision for adjusting the various movable parts of the filter, and of controlling their movements, as to reconcile the filter as a whole for use with an adjustable timing device for controlling the exposure of the pllate. so that a relatively short exposure of t e plate is associated with a correspondingly short period during which the action of the movable parts of the filter can have any effect upon the X-rays, the speed of travel of the grids being thus related to the time of exposure, and the turning movement of each slat being slow or rapid according to the time allowed for ex posure. i

VIII. To provide a special connection between the timing mechanism-and the inevableparts of the filter to enable the movable parts of the filter to be driven by themovable. parts of the timin mechanism.

IX. To interpose between V the timing m chanism and the movable parts; of the filter a connecting member the len th of which is varied autom tically and to en ex' tent eonttollahl e by chance, 30- to enable the grids to l e-brought toe-udstart'ed from positions Whicllfaie nfice'rteiir'and haphazard; sorbet for photogmihie wor lr of a. kind requiring repetition of "exposures, shadows-cannot to custom the plate in conse uence of any fixed'nes inthe positions of the sl atsat the beglnniiigor end of the ex 'os'ilres'i i r To provide variousparts and combinations thereof for increasing-the general of ficienc 'o'ithe filter mechanism. e

Reference is made to theaccomp'ahying drawingsfformi'ng i part of this specificatimt'anu inwhich like referenc numerals indicate like parts throu hout-e11 of the figures.

Figure 1 is a plan view of m improved Xmy filter and a timing device connected Por'ufse therewith. v

Figure'2 is a sect-amen the line 2-2 of Figure 1, looking in the direction indicated by the arrows. v V

Figure 3 is a plan view'of the lower grid and parts immediately associated therewith.

Figure 4 is a, fragm ntar horizontal section, showing parts appearing in the upper' portion of Figure 3.

Figure 5 is a section on the line 55 of Figure 3, looking in the direction indicated by the arrows.

Figure 6 is "a section on the line 6-6 of Figure 3, looking in the direction indicated by the arrows.

Figure 7 is a plan view of the timing mechanism as adapted for use with my improved filler.

IOU

tilting bar 37 has a slight tilting or rocking movement upon the bracket 40 as n center, this rocking movement being limited by the bracket 41. When, therefore, the scr'ew 38 is adjusted, the tilting bar 37 is affected acco'rclingly, so as to be slightly tilted in difierent positions and held in such positions until further adjustment of the screw.

Since the side wall 32 is stationary, and since the several cranks 35 extend through the openings 33 and into the slot 36 of the tilting beam 37, it follows that the tilting movements of this tilting beam, under control of the adjusting screw 38, must afl'ect the various cranks 35, and must affect them in slightly diti'e'rent ways and to different extents. t also follows that all of the slats 34 must be correspondingly afiected. Thus with the tilting beam 37 in one posit-ionlhe slats 3% might occupy the positions indicated for ihoni respectively in Figure-2. If, however, with the slats occupying such positions the atljusting screw 38 be turned, sons to depiiass are adjacent c'nd'of the tilting beam 37 (see Figure 6) and thus 'to raisetheiopposite end of the tilting beam,- the slats 34Xvill affected by this adjustment. Thatis to say, the slats which are farthest tothei'i Ht 950- cording to Figure 2 are eabli tiii'neds 'ghtly in s eontra elockwise dirsetionqthgsiats farthest to the left according to this bein turned slightly in a clockwise diiection an all of the intermediate slats exeept those in" the proximate "middle ofthe figure, are also i turned slightly, the degree of rotation bein less and less'the'closerthe'slatsere-located to the middle- Aga'imif the adjusting jscr'ew' 45 hml extending 't 'oughthis'zslotiis a pinres mes by the'. 'zfzrairre The :bell' heri'providerl with a slo'ti'i'f, and exten'dizigrrthioughthis slot-is ziin; SfifiThiS' pini48' is carried ibyrenotlie'r grid frani' 349, similar to the: grid frame 2 be turned in the direction opposite' to thebne in which it had been turned 'befjoreg'the reverse action takes; slets :being turned slightly as-be ore, but'in theopposite direction of rotation: Thus the extent of in p clination between consecutive slats may within reasonable limits bevaried at the will of 'theoperator. (The partsijust described are so proportioned end arranged that whatever be the adjustment of the screw 38 and Whatever be the position of the tilting beam 37 relatively to the frame, the planes of all the "slats always extend in such directions that all of'the slats are ekac'tly edge ercnce to some particular pomtefilittle distance above the apparatus, 'the distance of such point above the slats, howeire'r, being inriable with different positions of'tlie tilt-- iug beam 37. Such being the case if 'an X- my tube be placed over the slats and in a fixed position, the operator may'by adjust- 3011b of the screw 38 so cause the slats to be iidjustecl that the plane of each slat extends straight toward the target of the X-iey tube. It also follows that if theX-ray t'ube be shifted to some other position aweyfrom or toward the slats, the operator by "simply adjusting the screw 38 can cause the slots to i ent speevlsof movement of thergn a ed upon a.-

' cital'ikulevev 42 isri "unelfiistoodsfrmn 1.

to the right hcc'ording to Figures 2 end 3, the slits are again turned slightly, but each in :1 contin clockx'vise direction. This the various s'lat's cuir'ied-by the grid franie have a tendency to extend toward the target of the X-i'uy tube, or at least to extend 't'oivu'rd a when point fixed i'eluti'rely to the frame.

T3 virtue of the arrangementjust described, the open spaces between 'the'slmrs are always open to their utmost limits for the purpose of enablin X-r'ays from the X-ray tribe 'to' pass tlimh 'hthefirfreely and withohtolisliruetion, an thet,'too, inde endently oTftlib uu'ious'posit-irons into'w'hieh the grid frame may be moved, the direction of its tmver r; the of its-finiteness; In other-words, the constr ction is such that the slits time a iwometi'cazlly in' order to accom m'ofiafithefnselvesto 'il-ifl'erent 'distfamces f the grid frame from the X-ray tube, as wen as' lio 'diil'erentwlistunees of 'trevel and'srdi-fli' be'll 'cranklever-'42'isjourn bolt-'43,:the'htter being mounted upon one eomer otfit'lre fr-tune 1'5: The-bell cranlr'lever is provided witli al oftiom 44' Buying a slot above describedg but'rr'nountedoiier the' latter dj x tendiflg orbsswiseztliereoiyas m y *rhez riaa fiiam 19 is enge g edt by guide wheels 50, mounted-imbnicketsfil and is edit ted to moire: in the direction of travel Thus it follow that whenever the grid frame '24 is by action ofthe lever 22 drawn to the left accordingto Figure 1,'the grid frame 49 is correspondingly drawn in a direction '10, but as they appear after the grids begin contact mechanism as; .opened;.t hel tube .oir-,

as es 9 .Figure '8 is a section on the line of a rod 23. This rodis also connected, with a Figure 7, looking in the direction indicated grid frame 24 const tuting a part of my imby the arrovvs j i proved X-ra. ffilter a-nd is sho vn morepap Figure-9 is aiyiew somewhat similarto ticularly igure 3. the right hand portion. of 'Figure 7, but

7 The grid frame124, showing the movable parts as occupying po- Wheels 25, and supported by these w ieels sitions different from those they occupy in in such manner thatthe grid'frame may said-Figure7. be moved rin the generalhdirection of'its Figure 10 isi a diagram indicating the length-that is, to the right and left acrelative positions and conditions of the cording to ig'ure 3, and with a. minimum grids and the contact mechanism for closof friction. A pivot 26 is, used for conis tnga'geaby ids ing the main circuit of the X-raytuhe, these necting the rod 23 with the grid frame 24,

parts being-shown as they appear normally in orderto allow for a slight lateral play while out of action and up to the moment of the rod 23, dueutoits connection with when the movable parts are thrown into the lever 22. The guide wheels 26 are supaction. portedby brackets 27, mounted upon the Figu Eigure frame 15. v jj; p 1 M I The gridirame 24 is provided with :1 their movements, and at the instant when pair of eyes 28, and extending through these the. contact mechanismcloseshthe tuloeVcireyes vare springs 29, supported upon the cuit. I: frame; 15 by appropriate-mountings 30. Figure ,12 is a,- diagram showing these These springs are 50 arranged as to be al-- same movable parts as they appear when ways under tension, so as to have a tendency the exposureis nearly jvfimshed, and -the toi-pull'zthe id frame; 24" to the right, accontactimechanism is-about-readyub open cordingu tqrFigurefi. 'Ilhepprpose of. these the tube; circuit. 1 2. springs is to'assistithetiming mechanismin, ,Figure. l3rishows the same parts e in, moving the rid frame-Q24, together with but.- as they appear. when .the.- grids ave varion'swmqyai re llshovvs sameparts as 1e finished their; respective movements and the controll able therebyi k llhegridairam flei s pr ide. i h a, ai ..e-t;=:-, f-s e walls 1;B2;;h he e era orm partly diam otthin stripsiand-made-p xneta referably iimanner-in't steel. =fIhe;-side-waI1- 32-;isfi-prov1 edfwith a cuit. 7.1555? ivi 4%; 'ui'" Figure) 1'4 is s a. side-elevation; grammati'cyshowingwtheegeneral which'myv device is i1sedm connectionwith numberfifiopeningsa33, 'eachcircular in an; X-ray. tubeuand -aiphotographieptable. form. as shown more articu1arl in3 Figure upon Elwhrcb media body-Lotta patientm. 54 z'lT-hese icircula-nfopenings are. arranged Aframe 21.5? madmixfianetal; prefeiiablypf in. a ,single row extendin ,i gmmise of steel, supportsz fiiostgzof-rthe; WorIcin tpartgethersideflwalliincluding tl1ei.timingirfiechanism =16:-- moons; -A numbermf islatsn34i zareisupportd by? trolling-r thehduratiomf'of thei period-during 1' thei side swells-13st, 32,,sill ld ;,;f0rj this purpose which .the' l-X-rayfitube isliniactiona ,iThis arehL-pr videdMWith ,rpintlsar=34 ;extending timing mechanisms: is of t the; general. type. throughnholes in the side v'valls n- Thus ithe disclosed i ini' iPatent I"No*.i1.-'1 ,209,273 -';d'ated;; slots are :journa-ledr iupon the side walls, and

ner s e inee ediwiths d Deer-19, 1916-, tonGharles- Fayer-g'zt e1con-.;so.adaptedmoaliennocked relatively,.;thereto.

Istruction "ando'actionazofeathe :beingmEachslat.:;34;carries' a..-crank 35, -secured:

modified to some I. extent} vas :hreinafter. rigidlynipon ita and-extending through some described, in order to adaptsitifo'rrzusei'in onenofsthe:adjacentlholesa33 intheside wall in connection with myifinventions. M", 32.".as.showmimoreflnarticularlv gin. Figures The timer is providedrzwithea 'knobullgwA-and h.

controllable at:the 'v'vi:ll ofitheoperatgriforv The cranksfilt extend outwardlybeyond controlling the duration 'of the; exposni'r thesidewall 32s,:for a' little distance, as indi- The timing'mechanism 'is further provided ecated Figure-:4; and i'nto' a slot 36 with with a cord 18-to be pulled byithe operator nvhich a'beam 37? isprovided. This beam has in order as set the timingi"'mechanism, 'an'd a slight tiltin movement andhence is known with anothercord 19 to be :pulled .by the -;as the tiltingheaml A screw 38 is connected 0 peril-tor I in order to release thei tim i'ngp with the tilting heamat a point adjacent one mechanism for purposes of an exposure. A 'end thereof, as indicated in Figure 6, and is pair of conductors 20', 21,= "COIlStltlltiIlg a: :used for tilting the tilting beam into slightly part of the circuit through the X ray' tube, different positions relatively to the plane 15 are energized and 'deenergi'zed by action of and for holding the'tilting beam in such pothe timer. The timing mechanism-is prosition. The screw 38 is thus an adjusting vided with a lever 22, hereinafter described screw. It extends through and is supported more particularly and adapted to make a' by a. bracket 39, mounted rigidly upon the single slow continuous movement during frame 15. There are two other brackets, 40

ear-h exposure. Connected with this lever is and 41, also mounted upon the frame. The

ggeoe i vided witlra hole 69,-andsvith a chaJmeIfiQf; which merges into this hole. The fevoluble stem 66 carries a' smiiI cam'TO, mounted; rigidly upon it, and adapted tq slowlyicove'r or uncover" the hole 69f :i'rid channeL-fitl,

T he snail cam earne t sleeve 71; and "en 19;the'snail'cam'fanda lug-74Yniounted'iipon settf" glever 95 is gand: into a passage 76 of substantially spring gfiiis to rock gaging this new i's'faas'pirn s ring. which eat-granny"' i esssinw" snail cam against the disk ,.68,- A lug 73 "cerr ied ,by

the spider bar' 62," serve limiting defining the limits of travel fo f;. th snail. i. H .l i if w 75 extends thi-ou gli'th 'spider' barf Aimfrusto-co ni cal form,;'the letter, eon netted 'with'andvirtiiall y ',.fornii r "a con-t tir'iuat'icnfof an air hole 7 the f xed; board 6415f the bellows. The hole fig and lchan'nel "69 also constitute an air hole through the fixed board 64 of the bellows.

The operator; by turning-the stem fidby means of the'handle 67,;can hningfthegsnailfl cam 70'into position topartiallg cover they, mdi

,-l1o l'eifi9andipassage fi9i, so as to restrict 11:0

any desired. extent thecepeeity .of the be1-,.-

lows for taking in air. .screvvgifi is :11 adjusted .forIf-urther controllingvithe air in takeof thebellowvghnd as described, is the means employed gfOlf controlling. with which the bellowsis ope H .A connecting vrod 78 tends rem" the movable boardheiisllews e gagement t with ithe rocking. lever, 2,2, for the,

p rpose .01"';actuating the, latterLjThe ibellows is provided with tenair zwaly'e Z9 with r cdve i s th t s ai mm The air valve ;isfnor mally opened whenever .the eordBQc S J11 tl1e,.,right according to .Eigure movement is. 01; the purpose oiper venting the hellows in order to. allow.v

its

movable parts to be quickly restored to 1 nor-.

lnalpositiom m r Y A frame 81-- supportsa,portion of the timing ,mechgnisin Mounted "upon this, frame. is :a shaft 82, unon .whicli-the'rocking lever 22 sis journaled. spiral spring,83 encircles the shaft .82, :endis connected with the rocking lever ,j 22,and mith thei frame in h enn r t he spr n s-elwaysi der tension," and that..-the; tendenqv. of the rocking lever: 22 .is vto'eroclr; in E a clockwise 1 r direction 7 according, toQFig-ure 7 m w a.

The rockingirleyer 22qcaries iarfcontacti plate 84, insulated by hlocks'86 made 10f insulating smaterial, the contact platetbei-ngprovided. with auzzontaot boss 85nand con nected with. .a. ,conductor 8'i .-leadin; 1' therefrom, to the QX ray tnbe, The contact ;'lever. 88 ferries a contact boss-89 mating the contact boss and-eadapted'gto; be brought intoiand out of contact therewith. The con-5: tact lever 88 is;.monnted ,upnn e;-.-pin- 90,

the m intake, w eiodically i carriedhy: the p cking lei/c1222, in such manner as to .be adapted to swing upon this pin cots" center '5' The contact lever' 88 ca1 ries am m ni ill, and connectednvith this amiss sgring 92, yvhich is a lso connected with an extending portion 93 of therock e his .Th m, 9 ,.4'9 sr s n a 1'sI IQfl} i nd e s he reinaft er: described.

iwi a d, t roc P091316 e s- A Q s r g 06, o ec rlwifili eecin le r ,1 used. o e puree .Q At ract ng t t ng. eve nt s rm l. PQ lWL The t ency Qfthe thesetting lever 95in a cloc lqvise directionaccording to Figure 7, vl1erea s a pull upon the cord 18 by hand is 2 .tenfl y .FQr IOFFk t e t ng. l -.91 in a contra clockwlse direct on according to this. figure. v

l lounted upon the frame 81 is a metallic finger 97. This finger is so positioned as to iheslidebly; engaged by the roller 94, as cated gin Figure 9. The finger 97 is adapted to -hold thecontact lever 88 in the position indicatedufor this lever in Figure 9,-for emoment after the releasing of the rockingflleverg22atthe beginning of each periodotexposure ,A conductor 98 is connected withthejzX-yay tube; along with the conductor- 81; above described.= 1

g A Ja'teh; 99 ris mounted-upon the frame 81,-;gndmarl'i'es a pin 1 00 extending laterally yfromwit and to? which the releasing c0rdt-19- issecunedg ,the. frame. v8 l-and.;-soi-posit'ioned that the gconteehdevei 88 can lodge against it 'whenelo sed hntgis ever thmg-peking lever 22 is rocked to the awn to-"limi -efutsutmvehfigia clockwise direction gaccprdingtoil igurhsl l lfhevopeisation of the timing mechanism may be liriefiy-desclibed as follows:

Ias above descrihedr The ndjustment thus pmd'e1c0ntrolsthe time period of the expoi snre;?in:that% it seontrolsithespeed at which the movable board 65 of the bellows can swing eu ary fromthegfixed heal-(r64 thereof; This ,ad iustmenthbeingmade,- the ,operator ;pull s hy hand nponztheqsetting cord 18. This ,i;ocks the vsettinglever 95 contra-clockwise nccording to-Figure 7.. ,This movement 0f tl im settin-g lever cal'ises the cord SOJto ,open gthe air valve Z9, .and also ca uses the contact lever 88 to he "moved bodily to the right according to F igure'f, so as to shift the rocking lever 22 to the limit of its travel ,in a vicontra-clocluvise direction, as indicated in Figure 9. This same movement of the parts brings the roller 94, carried by the arm tll, into engagement with the finger 97. This prevents the contuct lever 88 from imv r m. i A- ,limiting stop, 101 is so mounted upon 7 Thca'lope'rator -first adjusts i the air inlet I mechanism; ,of :the bellows 64, which he does by tunilng-1the; handle .67 anduthe screw 75 as to control the roc slats 52, in the same manner that the tilting bar 37 is adjusted to control 'the rocking lateralto the direction of travel of the grid frame j 24; and when the grid frame 24 makes its reverse movement, that is, when it moves to the right "according to Figure 1,

the grid frame 49 is moved indirection contrary=to the one in which itwas moved as just stated; The relative movements of the grid frames 24 and 49 may be understood by a study of Figures 10 to 13 inclusive.

Located adjacent thegrid frame 9, to

the ri ht of the same according to Figure 1,

is a ti ting beam 53 like the tiltin beam 37 above described. A row of cran 54 are disposed adjacent the tilting beam 53, and extend into the slot thereof, as above described with-reference to the manner in which the cranks fit into the slot 36. The tiltin an a justing screw 55, revolubly mounted in a bracket 56, after the manner of the screw 38, mounted in the bracket 39 above described.

The operator, by adjusting the screw 55, can adjust-the tiltm bar- 53 in such manner ring movements of the the target of the X-ray'tube, any movement or movements made by'the gridfra'meswill be so co-related with rocking-movements of the two sets of slats 34 and52that'the slats will rock so:as to continue to extend-directly ed ewise toward the tube target. "In fact, eac individual slat, wherever found in either grid frame, has a compositional movement so'arranged that' no amount of sliding of the grid frames back and'forth can cause the slat to do anythingelse except keep itsstraight toward the general plane extending tube target. j

Such being the casefit follows that the spaces between the slats'ofler-the best possible paths for 'X-rays from the tube target to pass through, but that theslats are more or less in the paths of the secondary X'rays; which emanate from a multiplicity of other points some distance below the X-ray tube. Usually the secondary X-rays radiate from the bones of a patient who rests on a table as indicated in Figure 14, and owing to the 'uondescript positions occupied by these bones, the secondary rays have not much chance to find their way unobstructed between the slats of the filter. Hence while some of the secondary rays get through the beam 53 is adjustable by -means of.

filter, the proportion of. such rays is small relative to the primary'X-rays which pass through.

I will now describe my device in its relation't'o the timing mcchanism-that is, to the mechanism used for timing the exposure of the sensitized film or plate to theaction of the X-rays.

While my device may be employed in connection with timing devices of various kinds, I prefer to use it in connection with timing devices of the type shown in Patent No. 1,209,273, dated Dec. 19, 1916, to Charles Fayer.

In order to elucidate the connection between my invention and the timing mechanism shown in the patent just mentioned,

I will brieflydescribe a portion of the timing mechanism, as shown in my Figures 7, 8 9.

The rod 23, used for actuating the grid frames as-above described is connected with the lever 22, which is the rocking lever of the timing device, in the manner indicated inFigure 7. 'The rod 23 is pivotally connected with a ratchet wheel 59, the latter being journaled' upon the rocking lever 22 and adapted to be turned. A spring pawl 60,

mounted upon the frame work, is detachably,

engaged to the ratchet wheel 59, so as to prevent retrograde turning ofthe ratchet wheel in one direction.

As a result of this. arrangement, .there is a certain amount of relative movement between therod 23 and the rocking lever 22, due to step by step rotation of the ratchet wheel 59, so that the rod 23 is virtually j lengthened and shortened, to an extent more or less haphazard. Such being the case,"the' grid frames do not alway's start from the same point, and the point trom which they do start is a matter of uncertainty.

The purpose of the arrangement just described is to prevent the movable slats from being repeatedly exposed in the same positio'nQj when the, device is used. for. repeating exposures. Suppose for instance, that. half llO a dozen short exposures are made .in succession. upon the same sensitized plate, as is frequently done in X-ray work. Manifestly, the metallic slats, are less apt to reduce objectional shadows .upon the film 1f the general positions of the grids and consequently of the slats carried thereby, are so shifted as'to occupy dilferentposiat the bottom. of Figurec 'l', the cont'act boss 85 moves out of engagementwith the contact boss 89, so that the tube circuit ,is thus opened, and is leftopen for' the,time'being. In Figures 10, 11, 12, 13,1 have indicated the several successive positions for the con-- tact mechanism used for energizing and deenergizing the tube circuit,,and have shown the. various relative-positions of the gridframes 24 and 49 as related to thedifi'erent positions ofthe contact mechanism.

Figure shows the condition of the tact mechanism, and the relative positions of the grid frames 24 and 49, at the instant;

when the timing mechanism is set, as.i ndi- 80,

position; and hence, the cord- 80 being recated in Figure 9,;by*theoperatorpulling laxed, the valve -79, used for venting, is and releasing the setting cord 18. It illbev closed. v I noted that while the contact bosses 85 and 8 9 1,

Supposen'ow that theoperator pulls upon are separated, the grid ,fra -f fl n .11 76; thereleasing cord.1 9. ;;This disengages the. in their extreme positionspthat isjthey are latch 99 from the contactplate 84, and thus at the limits of their travel.- respectivelvc-in releases;the;rocking 183781122. The, rockingone direction'of travel,

lever22'nowturns-slowly in a clockwisei di- In Figure- 11, tl1e, same.parts ;are shovvn asreotion, at; a rate of speed determined by. the they appea diate yrizthe-rele se 2 air' inlet oithebellqws, this being adjusted, takes place. Thegrid frames 24 and 4:95amall as abWeLdescribed. The contact lever 88, now in motion, travelling inztvnogdirections by itsmo'vementaway from the finger 97 crossing each otheg and the contactibosses now causes the-,disengagement;othe rollerv 89 rein, g men 94; front-the finger 91, butnotuntil therock In Figure 5 12, t e progressivsmomment; a ng nae-221.1135 i xe tedr -a -portio f its, of the respectiveigridtfr -me eisii llaw iw fic rockingstrgkelbackgtowarditsnormalposi;; itt ei heni the contflgt b ti o1Ei,-;and up tmthi'stimethej contact bosses;- being still in engagement, 7 H 85n-andi-89istill' rem ;s paratel-.;.As-s n,a .l ,:Eigure 3\,. g id fl me hevel ach however as the roller'94 is disconnected from; finished, this bodily movementand reafiede =zthe- -finger;97-, the contactvlever-r88 is leftiree their normal positionthe contact,- mgrnbersJQQ to swing relatively to theflrocking lever 22, 85, 89 be g-now s pam i c l sothat thetubej; and;under tensionof-tthe spring 92 theconcircuit; is open; tact{;lever-88;1 n P i u h pos tion asat h T-T W l1 bp 9 6$1 thew n etnes s t ie 0 t -c8 -;I.o g gain t'the: 1 frames 4% ar alw ys n-mqtienivhile the:

-1.: contacts bnssi l i mThi wQ O J e-i circuit J tu e ina ie ithamewmee ntthe5;

thmu hethefii-ray :tu e; nd. vitii p y ussfid: frameiar -n tlrer:qil ckinq irier rhbut thtzgt e closure oflth'e circuitdoes not-take',relativelyslow and uiiiforlni gltgw ill alsmhe place until afterthe"; ocki g.- "l vee 1 1 s inted. :that, th rock ng ime em n ivotz t e? motion! wtllhis lie-Jan i po 'ta fip n v s slats: a l e y ar neie erioemeansllihatithe grid framesabovejdescribedg-lsome positions-10f the X rayt,l1be1 t iliqg qm in .qmakingnthein? slidingmovements=under, ,other positions thI:QQff-.E,Thatuj$ to, sam the control :so'f ethe; rocking=r lever:.22, iare acg operatorg by.adjustingethescrews 3,8, and wall emovin and; that the Y slats car,- ;.'as above described;can;sondjust-thegocking ried by them'are-actuallyjturned, at;the in-'- movements of.- th-eslats itha-tvfthe slats in yr;

50 'stant whenthe X'I'fiY'ztllbQ'Cil'CllitiS closed. rocking, 'turnmorea-raprdly it; thegX-rayjla, This prevents the slats .-;froinx beings-inf fixed .-'--tube, is ;;-in" close proximit -;to -,the;fil ten-meclr-.- positionsat3the;time whenitheE-X-raysfare anism-than :ifa-little;; 1rther axvavthereturned-on.-r ;Thus an shadows-cast;bythe -from.-;.- i1 slats c'an-dono material-'harmi' towardiafi'ect- An X-ray tube-as;shownl i vl giifi- 51mg the sensitized-plate or .film toywhich the provided-With; a target 103, as;ma-y been- ,12 1 X-rays are'wdirected. 1 derstood frorm Figure;'.14 ThQibOdymf-r a pattientjs-shontn at 104.; -'As :may readily} The same movement ofitherocking lever 22;being continued, however; brings the con-' be, understoodcfrom theyfigure ust men,

tioned, the pri mary'rayshaves much better tactleven 88:into engagement with the limiting"s top '101,'-,but' at an instant before the rocking lever 22wreaches the limit of its stroke.--: The resultis that since the rocking lever 22 continues its movement to the end of its stroke, and since the contact lever 8.8 is 95 abruptly stopped in its 7 travel as indicated mediately executing a retrograde move ment. That is -tosay, the contact lever 88, because of the engagement of the .roller. 94 with the; finger 97, is turned slightly in relation to the rocking lever, 22,,because the setting lever 95 rocks back into its normal position. The rocking lever;-,22 starts-to rock backwardly, toward its normal position, but is unableto do so because the; contact plate 84 is held by the latch 99. The device will remain any length of time in the condition. just described. The contact bosses 85 and 89 are now separated, and consequentlv the electric circuit through the X-ray tube is open. Thesetting lever ,isin its. normal con-..

nism than is the case with, such secondary. rays as may emanatefrom-,the bones of the I do not limit myself to: the-precise mech-- anism shown, as variations ma; be; made g l30.

chanceof 'gettingthrough the filter mecha 12 l at a rate of speed dependent therein'witho'ut departing from my inven tion, the scope of which is commensurate with my claims.

Having thus described my invention, what I claim as new and desire to secure by LettersPatent is as follows:

*1. In an X-ray filter the combination, with a framework and a grid frame carried by said framework and movable relativelytliereto'back and forth in -a predetermined plane, of -'a 'plurality of slatsnfounted iipon said grid"frame and made of mater-n1 qpagu to X -rays, saidslats beinginclined to ifl'erent angles relativelyto;said grid frame," and means for causing said slats to roekjwhilesaid gridfra'me is} rhotionfl in order to facilitate "the -fiassage between said of rimar X- rfaysf remittingslime'iily from' s'aid X-raytubef" 2. In 'j'an' X-ray *filteithe; co'uibi' ati on, with a' framework and ,a fmusmoanrea upon said framework an movable'rlaitive ly thereto in a predetermined plane-5613a pl'u rality I of slats jou'rn'aled' upon" "saidgrid frame a d made' of material epai ue ur X'-rays, said slats being'"'s" aced "aparwte" allow thepassage betWeen' -t eni ofpriiiiary X-rays from the Xaaymbe',and-'meh nism connected with said grid "frame and with said slats for" making-sausages a rate of speed commensurate with "the speed of travel of'the gridj'frain''eL-i an, an 'X-jray filter-aha-emanation,

with a. framework and a rid frame mounted upon said framework'an movable relativelythereto in a predetermined plane, ofa.'plurality of slats carried by saidgg'r-id fi-arr e and made of materiaPWpaque to re-rays, said slats beingspaced'ap'art toallow the passage between thein-of'jprimary xgrsys' directly from the X- ray'"tube'," and =me ha-" nism connected with" said slats and with" said grid frame and'driven by movements" of said grid frame for rocking said slats of travel of the grid framefl .l

4. In an X-ray filter the combination, with a framework and a grid fframe mounted upon said framework and movable relatively thereto in a predetermined. *plane',' of a plu rality of slalts carried =by"' s'aid grid frameand made of material opaque to X-rays, said slats beingC allow primary -ra'ys from'the X-raytube to pass between, means for rocking s'a1df slats at a rate of speed commensuratewith the speed of travel of the grid frame, and mechanism controllable at the will "of the operator for adjusting the rate of speed' at which said slats are rocked, relative to the speed of travel of the grid frame.

In an X-ray filter the combination. with a framework and agrid frame mounted upon said framework and movable relatively thereto in apredetermined plane, -of a plusi th p d.

a -1 rid frame crossing the slats of anspaced apart in order to -gr rality of slats journaled upon said grid framefand made of material opaque to X- rays, said slats being spaced apart to allow primary 'X-rays from the X-ray tube to pass freely'between them, and mechanism connected with said rid frame and with said slats,'a'nd 'contro lable at the will of the operator for shifting said slats respectively to different angles relatively to the grid frame, in order to render said slats exactly edgewise' in position relatively to different positions occupied by said X-ray 1'6." In an "X-ray filter the combination, with'afra'mework'and a grid frame mounted upon-said framework and movable relatively therto'in-a predetermined plane,'of a plurality of slats carried by said frame and made bf iiiaterialxopaque to X-rays, said slats beingspaced apart and tilted to difrarest single relatively to the plane of the g rijd franie in order to permit the passage fi xi g g from the X-ray tube and between the slat s,"a of cranks one connected itIi each 'slat 'for-Ifockingthe same, a tiltiiig" beam "common to all of said slats and pitivdded -with a; slot into which said cranks extnd,"sali d tiltingb'eain being sup orted upon said Ffiameworkand located a jacentsaid gri'cl'*frame,' and=means controllable at the wilrtsrthe'operator for tilting said tilting 4min to slightly different angles; relativel'y' to'the plane oi the grid frame in order w-vai the 'i' aite'of speedat which said slats are rocked relativelyfto the speed of travel of 'said'grid fmmem v '7. In 'anf Xray filter the combination, with"an- X-'ray tubeand a framework disposed gadj'acent thereto of a plurality of gridjfranies mounted upon said framework and each *mojvable relatively thereto in a difif'erent plane, the planes crossing each other so that the grid frames travel in directions crossing each other, a plurality of slats carried 'by each grid frame, the slats of other grid frame, and connections for causing said grid frames to move simultaneously with reference to the framework.

8. In an X-ray filter the combination, with an X -ray tube and a framework disposed adjacent thereto, of a plurality of id frames moun'tedupon said framework and each movable relatively thereto in a difierent plane, the planes crossing each other so that the grid frames travel in cross directions, a plurality of slats carried by eachof said gridframes, the slats of one grid frame crossing the slats of another grid rame, connections for causing said grid -'fra1nes to move simultaneously with reference to the framework, and means controllable bymovements of the grid frames for causing said slats to rock relatively to the grid frames whereby they are carried.

9. In an X-ray filter the combination of a framework, a pair of grid frames each mounted thereupon and movable relatively thereto in apredetermined plane, the

lane in which one rid frame moves crossmg the plane in which the other grid frame moves, a plurality of slats carried by each grid frame and opaque to X-rays, the slats of each grid frame being spaced apart in order to allow X-rays from a predetermined point to ass freely between them and yet to reduce t e number of secondary X-rays tending to pass between them from points other than said predetermined point, connections for enabling the movements of one of said grid frames to actuate the other of said grid frames, and mechanism controllable by movements of the respective grid frames for rocking the slats carried by the grid frames, respectively.

10. In an X-ray filter the combination of a framework, a air of rid frames mounted thereupon an movab e relatively thereto in different directions crossing each other, a plurality of filtering members carried by said grid frame and opaque to X-rays, these filtering members being spaced apart in order to allow X-rays from a predetermined point to ass between them and yet to reduce the number of X-ra s tending to pass be tween them from other points, connections for causing said grid frames to move simultaneously and connections from said grid frames to said filterin members for enabling movements of sai grid frames to shift the positions of said filtering members rela tive y to said grid frames, in order to maintain said filtering members in proper aline ment with a source of primary X-rays.

11. In the X-ray art the combination of an X-ray tube, timing mechanism connected with said X-ra tube for controlling the period during w ich the X-ray tube is to be ener ized for the pur ose of making a radiograp or the like, fi ter mechanism located between the X-ray tube and the surface where the radiograph or the like is to be made, said filter mechanism being provided with a pair of movable members mounted respectively in paths crossing each other for the purpose of sifting out secondary X-rays while permitting primary X-rays to pass through the filter mechanism, means for shifting said movable members alon said paths thus crossing each other, an connections from said filter mechanism to the timing mechanism, so arranged that both of said movable members are always in action before the X-ray tube is energized, and remain in action for a moment after the X-ray tube is deenergized.

12. In a device of the character described, the combination of an X-ray tube, an electric circuit connected with said X-ray tube for energizing the same, timing mechanism connected with said electric circuit and controllable by the operator for. predeterminin the time period durin which the circuit is to remain clos filter mechanism provided with a plurality of movable arts for filtering out secondary X-rays while permittin the passage of primary X-rays, said mova 1e parts being mounted to move along a plurality of paths crossing each other, means for actuating said filter mechanism during the entire period of time while the circuit is closed, and mechanism for maintainin the movements of the movable parts 0 said filter mechanism for a moment later than the expiration of said period oftime, so that the movement of said movable parts of the filter mechanism is continued after the said circuit is de-energized.

13. In an X-ray filter the combination, with an X-ray tube and a frame work disposed adjacent thereto, of a plurality of grid frames mounted upon said frame work and each movable relatively thereto in a different }plane, the (planes crossing each other so t at said gri frames travel in directions crossin each other, and connections for causing sai grid frame to move simultaneously with reference to the framework.

ARTHUR MUTSCHELLER. 

